I’m hyped for this TBH.
IMO Dune is a 3 part story, where the first book is parts 1 and 2 and Messiah is part 3. Look at the book lengths and you’ll see what I mean, book 2 is obviously much shorter than the rest and a I kind of epilogue to the first book.
There are the other sequels, yes, with their own conversation about whether they’re worth reading. But in so many ways book 2 really finishes the story and idea of book 1 that I like to think of it as just part 3.
So that they’re doing a trilogy in the same way is awesome IMO!
The theory I’ve heard touted is that the Villanueva trilogy will just follow Paul’s story. That arc concludes nicely at the end of Messiah and potentially sets up a 4th installment focusing on the kids if the appetite is still there.